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	<head>
		<title>three.js webgl - custom attributes [lines]</title>
		<meta charset="utf-8">
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	<body>
		<div id="info"><a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> - custom attributes example</div>
		<div id="container"></div>

		<script type="x-shader/x-vertex" id="vertexshader">

			uniform float amplitude;

			attribute vec3 displacement;
			attribute vec3 customColor;

			varying vec3 vColor;

			void main() {

				vec3 newPosition = position + amplitude * displacement;

				vColor = customColor;

				gl_Position = projectionMatrix * modelViewMatrix * vec4( newPosition, 1.0 );

			}

		</script>

		<script type="x-shader/x-fragment" id="fragmentshader">

			uniform vec3 color;
			uniform float opacity;

			varying vec3 vColor;

			void main() {

				gl_FragColor = vec4( vColor * color, opacity );

			}

		</script>

		<script type="module">

			import * as THREE from '../build/three.module.js';

			import { FontLoader } from './jsm/loaders/FontLoader.js';
			import { TextGeometry } from './jsm/geometries/TextGeometry.js';

			import Stats from './jsm/libs/stats.module.js';

			let renderer, scene, camera, stats;

			let line, uniforms;

			const loader = new FontLoader();
			loader.load( 'fonts/helvetiker_bold.typeface.json', function ( font ) {

				init( font );
				animate();

			} );

			function init( font ) {

				camera = new THREE.PerspectiveCamera( 30, window.innerWidth / window.innerHeight, 1, 10000 );
				camera.position.z = 400;

				scene = new THREE.Scene();
				scene.background = new THREE.Color( 0x050505 );

				uniforms = {

					amplitude: { value: 5.0 },
					opacity: { value: 0.3 },
					color: { value: new THREE.Color( 0xffffff ) }

				};

				const shaderMaterial = new THREE.ShaderMaterial( {

					uniforms: uniforms,
					vertexShader: document.getElementById( 'vertexshader' ).textContent,
					fragmentShader: document.getElementById( 'fragmentshader' ).textContent,
					blending: THREE.AdditiveBlending,
					depthTest: false,
					transparent: true

				} );


				const geometry = new TextGeometry( 'three.js', {

					font: font,

					size: 50,
					height: 15,
					curveSegments: 10,

					bevelThickness: 5,
					bevelSize: 1.5,
					bevelEnabled: true,
					bevelSegments: 10,

				} );

				geometry.center();

				const count = geometry.attributes.position.count;

				const displacement = new THREE.Float32BufferAttribute( count * 3, 3 );
				geometry.setAttribute( 'displacement', displacement );

				const customColor = new THREE.Float32BufferAttribute( count * 3, 3 );
				geometry.setAttribute( 'customColor', customColor );

				const color = new THREE.Color( 0xffffff );

				for ( let i = 0, l = customColor.count; i < l; i ++ ) {

					color.setHSL( i / l, 0.5, 0.5 );
					color.toArray( customColor.array, i * customColor.itemSize );

				}

				line = new THREE.Line( geometry, shaderMaterial );
				line.rotation.x = 0.2;
				scene.add( line );

				renderer = new THREE.WebGLRenderer( { antialias: true } );
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );

				const container = document.getElementById( 'container' );
				container.appendChild( renderer.domElement );

				stats = new Stats();
				container.appendChild( stats.dom );

				//

				window.addEventListener( 'resize', onWindowResize );

			}

			function onWindowResize() {

				camera.aspect = window.innerWidth / window.innerHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( window.innerWidth, window.innerHeight );

			}

			function animate() {

				requestAnimationFrame( animate );

				render();
				stats.update();

			}

			function render() {

				const time = Date.now() * 0.001;

				line.rotation.y = 0.25 * time;

				uniforms.amplitude.value = Math.sin( 0.5 * time );
				uniforms.color.value.offsetHSL( 0.0005, 0, 0 );

				const attributes = line.geometry.attributes;
				const array = attributes.displacement.array;

				for ( let i = 0, l = array.length; i < l; i += 3 ) {

					array[ i ] += 0.3 * ( 0.5 - Math.random() );
					array[ i + 1 ] += 0.3 * ( 0.5 - Math.random() );
					array[ i + 2 ] += 0.3 * ( 0.5 - Math.random() );

				}

				attributes.displacement.needsUpdate = true;

				renderer.render( scene, camera );

			}


		</script>

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